Needs review: the intro notes that the canning/enclosing process differs by cell format, but only pouch-cell challenges are detailed below. Cylindrical and prismatic can-specific challenges (e.g. can drawing/deep-draw defects, header/can seam issues) are not yet covered.
The electrodes either as a roll or pack of stacked layers are loaded into the can or pouch. Depending on the cell format will change how this canning or enclosing process is completed.
Challenges
- Ensuring no debris in can
- Ensuring no damage to jelly roll or stack
- Pouch
- Pouch Cup formation – avoid die inclusions
- Stack placement in pouch – alignment
- 2nd Pouch (over) cup – avoid die inclusions
- Heat Sealing integrity time, applied energy – avoid heater bar contamination affecting seal integrity
- Open cell seal handling prior to injection
- Pouch Taping – a line of tape applied on inner side of cup corresponding to placement of stack
- Isolation Testing
- HiPot testing or Capacitance tests are done at this stage to establish the integrity of the cell, this should find:
- debris / metallic foreign particles
- folds in the separator
- holes in the separator
- burrs on current collectors
- HiPot testing or Capacitance tests are done at this stage to establish the integrity of the cell, this should find: